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To ensure the financial viability of powder-based additive manufacturing technologies, the recycling of powders is common practice. This paper shows the lifecycle of metal powder in additive manufacturing, investigating powder manufacture, powder usage, mechanisms of powder degradation and the usage of end-of-life powder. Degradation of powders resulting from repeated reuses was found to be a widespread problem; components produced from heavily reused powders are typically of a lower quality, eventually rendering the powder unusable in additive manufacturing. Powder degradation was found to be dependent on many variables, preventing the identification of a definitive end-of-life point for powders. The most accurate method of determining powder quality was found to be the production and analysis of components using these powders. Uses for degraded powder had not been previously identified in literature, warranting the investigation of potential solutions to prevent powder waste. Amongst other waste-reducing solutions, plasma spheroidisation was identified as a promising method to avoid powder disposal for approximately 12.5% of produced powders, creating particles similar to virgin powder from end-of-life powder. Returning end-of-life powders to the supplier for upcycling may be the only financially viable solution to reduce waste within the industry. The compilation of research within this paper aims to enable users of additive manufacturing to conduct further research and development into powder upcycling.

Realistic representation of time‐dependent internal stress progression and deformation behavior of a potato tuber during a sample drop case has been studied in this article. A reverse engineering approach, compressive tests, slow motion camera records and finite element analysis (FEA) were employed to analyze the drop case deformation behavior of a sample potato tuber. Simulation results provided useful numerical data and stress distribution visuals. The numerical results are presented in a format that can be used for the determination of bruise susceptibility magnitude on solid‐like agricultural products during drop case. The visual observations revealed that slow motion camera images and simulation printouts were in good correlation. The modulus of elasticity of the potato specimens was calculated from experimental data to be 3.12 MPa and simulation results showed that the maximum equivalent stress was 0.526 MPa on the tuber. This value for stress indicates that bruising is not likely on the tuber under a pre‐defined drop height. In order to test the simulation accuracy, empirical, and simulation‐based estimates for total energy in this drop case were compared. The relative difference between empirical and simulation results was 1.27%. This study provide a good “how to do” guide to further research on the utilization of (FEM)‐based time‐dependent simulation approach in complex mechanical impact based damaging analyses and industry focused applications related to solid‐like agricultural products such as potato. Practical applications The engineering simulation based “how to do” pathway presented in this study is a scientific novelty because the explicit dynamics simulation technique for potato tuber damage under drop case and its visual verification has been limitedly introduced in the literature. This study present deeper analysis on material model description, slow motion camera records, time dependent non‐linear stress analysis and FEM based Explicit Dynamics Simulation procedures. This study aims to represent a realistic non‐linear deformation case of the tuber which is very complicated to obtain through physical and/or empirical expressions. As a further step from other literature studies, this research has presented a novel realistic time‐dependent non‐linear drop test simulation based on physical compressive material test data. The findings have been prepared in a form which may be used as input parameters in design studies for solid‐like agricultural products (such as potato tubers) processing machinery systems used in food/agricultural industries.

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This paper presents the results of an investigation on internal stress progression and the explicit dynamics simulation of the bruising behavior of potato tubers under dynamic mechanical collision. Physical measurements, mechanical tests, advanced solid modeling, and engineering simulation techniques were utilized in the study. The tuber samples used in the simulation were reverse engineered and finite element analysis (FEA) was set up to simulate the collision-based bruising behavior of the potato tubers. The total number of identical tuber models used in the simulation was

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Determining the mechanical properties of the parts manufactured from additive manufacturing (AM) technology is important for manufacture end-use functional parts, known as rapid manufacturing (RM). It is important, within RM design, to verify to some degree of confidence that a part designed to be manufactured using this technology will be suitable and fit to function as intended, prior to committing to manufacture. The method of doing this is to perform physical testing on fabricated parts and validate via finite element analysis (FEA) on the parts.

In this research, experimental field tests and an advanced computer aided design and engineering (CAD and CAE) based application algorithm was developed and tested. The algorithm was put into practice through a case study on the strength-based structural design analysis of a Para-Plow tillage tool. Para-Plow is an effective tractor attached tillage tool utilised as an alternative to the conventional deep tillage tools used in agricultural tillage operations. During heavy tillage operations, the Para-Plow experiences highly dynamic soil reaction forces which may cause undesired deformations and functional failures on its structural elements. Here, prediction of the deformation behaviour of the tool structure during tillage operation in order to describe optimum structural design parameters for the tool elements and produce a functionally durable tool become an important issue. In the field experiments, draft force and strain-gauge based measurements on the tool were carried out simultaneously. Subsequently, Finite Element Method based stress analysis (FEA) were employed in order to simulate deformation behaviour of the tool under consideration of the maximum loading (worst-case scenario) conditions tested in the field. In the field experiments, average and maximum resultant draft forces were measured as 33,514 N and 51,716 N respectively. The FEA revealed that the maximum deformation value of the tool was 9.768 mm and the maximum stress values impart a change on the most critical structural elements of between 50 and 150 MPa under a worst-case loading scenario. Additionally, a validation study revealed that minimum and maximum relative differences for the equivalent stress values between experimental and simulation results were 5.17 % and 30.19 % respectively. This indicated that the results obtained from both the experimental and simulation are reasonably in union and there were no signs of plastic deformation on the Para-Plow elements (according to the material yield point) under pre-defined loading conditions and a structural optimisation on some of the structural elements may also be possible.This research provides a useful strategy for informing further research on complicated stress and deformation analyses of related agricultural equipment and machinery through experimental and advanced CAE techniques.